My darling sister died four years ago, when she knew she was dying she said would I look out for her son (he was 29 at the time) as I have always adored him. Four years on and we have no contact, he lives up north and we are down south. I always remember his birthday and Christmas with presents and cards and try to reach out but don't get anything in return. His dad met a new woman soon after my sister died and they are planning to get married. My nephew keeps in touch with my cousin who is his god mum but never gets in touch with me or my brother his blood family. My mum (his grandma) is ill with dementia but he never gets in touch to see how she is and has told my cousin that he feels she has already died, quite hurtful. In essence I feel like I am flogging a dead horse and that we have been airbrushed out of his life and don't know whether to carry on sending birthday and Christmas gifts. He is getting married next year and we have all been invited which surprised me but I do feel very hurt. I promised my sister I would look out for him but he is a grown man now!! AIBU??